Aristotle · a new plain-English translation from the original language
1| In quartan fevers one should not thin the body down, but instead build fire into the body by what one brings in. One should also make use of exercises. On the day of the attack, after bathing, one should not seek sleep. And for this reason a heating regimen is beneficial, because the quartan fever is weak — for if it were not weak, it would not have become quartan. Do you see? Where there is a great fire, a lamp cannot go on burning, for the great draws the small to itself. For this reason one should build a great fire into the body, because the fever has only a little fire. Now the daily regimen consists in bringing fire on the one hand and moisture on the other into the body. And diseases are of two kinds, some from fire, some from moisture. Diseases from fire are cured by moisture, and diseases from moisture by fire; for fire dries up moisture. Book 2. Problems Concerning Sweat. Why does sweat occur neither when we hold our breath tightly nor when we simply hold it, but rather when we let it go? Is it because breath held in fills the veins, so that it prevents the moisture from getting out, just as water from water-clocks is prevented when someone stops them up while they are full? But when the breath does get out, a great deal of sweat results, because during the stoppage it has been collecting little by little within.
2| Why do parts of the body immersed in hot water not sweat, even if they are hot? Is it because the water prevents the flesh from being dissolved, and sweat is the badly-attached material built up in the flesh, which is prevented from being dissolved when it is being excreted on account of heat? Why is sweat salty? Is it because it comes about through motion and heat, which separate out whatever is foreign present in the union of nourishment with blood and flesh? For this foreign material separates off most quickly, because it is not proper to the body, and it exudes outward. And it is salty because the sweetest and lightest part is expended into the body, while the most foreign and most undigested part is released. Such matter, when it collects below, is called urine, and in the flesh, sweat; both are salty for the same cause. Why do the upper parts sweat more than the lower? Is it because what is hot rises and is above, and this carries the moisture upward? Or is it because breath produces sweat, and breath is in the upper parts? Or is it because sweat is undigested moisture, and such moisture is in the upper parts, since the blending of elements is upward?
3| Why, when we exercise, do our hands sweat the most, if we keep everything else in the same posture? Is it because we exert our strength most in that part? For it is with this part, being nearest to the source of strength, that we hold our breath; and when working hard we exert more strength, and being in this state we hold our breath more. Further, we labor along with the part being rubbed more than when some other part is rubbed; for through the retention of breath we exercise ourselves both by being rubbed and by rubbing. Why does sweat from the head either not smell or smell less than sweat from the rest of the body? Is it because the region of the head breathes well? This is shown by its being porous, as is evident from the growth of hair there. But regions, and the things in them, become foul-smelling wherever they do not breathe well. Why do those exercising sweat more if they wrestle after resting in between than if they wrestle continuously? Is it because sweat collects during the rests, and the subsequent wrestling then draws this sweat out, whereas continuous exercise dries it up, as the sun does? Why do people sweat more when they have not used sweat-baths for a long time? Is it because sweating comes about not only through moisture but also because the pores are opened wider and the body is looser? So in those who do not use them the pores are closed up, while in those who do use them the pores are opened.
4| Why, when the sun heats the naked more than the clothed, do the clothed sweat more? Is it because the sun, by scorching, closes up the pores? Or is it because it dries up the vapors? These effects occur less in those who are clothed. Why do faces sweat the most? Is it because they are especially loose and moist, and sweat passes through such parts? The head seems to be a spring of moisture; this is why the hairs too grow there, on account of the abundance of moisture. And the region is loose and thin, so moisture naturally passes through it. Why do people not sweat more when the fire is applied all at once, nor always less as it is applied in a smaller amount, but rather when more is brought to bear over time? For those in sweat-rooms sweat more than they would if that much heat were applied all at once. Is it because each thing produces its effect in due proportion? So if a given amount produces the effect, a greater amount will not produce more effect, but rather the opposite, because it is by being in due proportion that the amount produces the effect. For this reason people do not sweat more in proportion to a greater amount of heat, but because a different proportion is required for each stage, what has already produced its effect no longer produces it when more is added. For the same thing does not both prepare the way for each stage and render it fit, and also, already, produce the effect — rather, one thing does one and another does the other. So a small amount rather than a large amount prepares the way and readies the body for sweating; a different, greater proportion is needed to produce the sweat itself. And this latter no longer does what the former did, but afterward does something else, being a different proportion.
5| Why does sweat flow more freely when people are scraped off with a strigil than if it is left to remain? Is it because of cooling from outside? Or is it because the sweat on the outside forms like a lid over the pores, so that it blocks the outward drive of the sweat from within? Why does rue make sweat foul-smelling, and so do some perfumes? Is it because those substances whose odor has a heaviness in it, when mixed with the excess moisture, make the smell more offensive? Why do we sweat on the back more than on the front? Is it because in the front there is an internal region into which the moisture can be channeled away, while in the back there is no such region, so the excretion must happen outward? The same cause explains why we sweat less on the belly than on the chest. Further, the back and the rear parts hold on to sweat more than the front parts do, because the front parts cool off more than the rear. This is also why the armpits sweat fastest and most: they cool off least. Further, the parts around the back are fleshier than the front, and so moister. And there is more moisture in the rear parts, since the marrow, running along the spine, supplies a great deal of moisture.
6| Why do we not sweat on the parts we lie on? Is it because the place we are touching, being made hot, prevents the sweat from passing through, since it dries it up? And further, it is pressed, and blood that is pressed is dispersed, and when this happens the part is cooled more. A sign of this is numbness: this affection is a kind of chilling, and it comes about from pressure or a blow. Why do people sweat more while asleep? Is it on account of counter-reaction? For the heat, being collected within, drives the moisture out. Why does the face sweat most, though it has the least flesh? Is it because the parts that sweat easily are those that are somewhat moist and porous, and the head is of this kind? For it has the greatest amount of moisture proper to itself. The veins stretching from it show this, and so do the catarrhs that come from it, and the brain being moist, and the passages being many. A sign that there are many passages is the hair, which reaches all the way out. So the sweat does not come from the lower parts but arises from the head. That is why the forehead sweats first and most: for it lies below the head first in order, and moisture flows downward, not upward. Why do people who are sweating feel nausea if they are chilled, whether by water or by wind? Is it that the moisture, being chilled, stood still in a mass, whereas before it was not at rest because it was flowing? Or is it also that the breath, as it passes out and becomes sweat through the chilling, is turned to moisture within before it gets out, once it is chilled inside, and by falling upon the stomach produces the nausea?
7| Why is it that when the head and the feet are heated, sweat comes from them most of all? Is it because the part that is heated draws the moisture to itself, and the moisture has nowhere to be used up, since these places are bony? So it falls out to the surface. Why do people who have been exerting themselves sweat when they stop? For if exertion is the cause, they ought to sweat while exerting themselves. Is it that during exertion the veins, being inflated by the breath, make the passages close together, while when they stop the veins subside, so that, the passages becoming wider, the moisture passes through more easily? Or is it that during exertion the motion separates off breath from the moisture that is naturally present, and because of the heat that comes from the motion the moisture becomes breath on the surface; but when a person stops exerting himself, the heat also ceases at the same time, and out of the breath, as it condenses, moisture is formed, which is called sweat? Should one prepare to sweat more in summer or in winter? Is it that, since people become more moist and more troublesome without care in winter, one would need it more in winter, when the change is great and the residues are not concocted along with the rest? But again, the winter condition, being chilled, is contrary to nature. So it is clear rather that one should do it more in summer; for indeed all moist things putrefy more in summer, and that is why one must draw them off then. This is also why the ancients, all of them, spoke in this way.
8| Why is it that, though the body is always flowing and there is always an efflux from the residues, the body is not made lighter unless it sweats off some moisture? Is it that the excretion is smaller? For when the moisture changes into air, more comes from less, since the moisture, being separated out, becomes greater in bulk; so the excretion takes a longer time, both for this reason and because the excretion passes through fewer passages. Further, the viscous and sticky matter is excreted along with the moisture because of its admixture with it, but is unable to be excreted along with the breath. This is above all what causes distress. That is why vomiting relieves more than sweating does, because vomits carry this matter out along with them, being thicker and more bodily. And also because this place, where the viscous and sticky matter is, is far from the flesh, so that it is a task to remove it from there, whereas it is near the stomach cavity, since it arises either in the stomach itself or close to it; that is also why it is otherwise hard to draw out. Why do people sweat less in the very act of exerting themselves than when they relax? Is it that while exerting themselves they are producing, while when they have exerted themselves they have produced? It is reasonable, then, that more is excreted then, for at one time it is coming to be, at the other it already is. Or is it that during exertion the passages of the flesh are closed up because the breath is held in check, and when people relax they open? That is also why people who hold their breath sweat less.
9| Why is it that when we are running, or when the body is in motion generally, the sweat is not greater, but rather when people stop? Is it that at that time it is possible, as if by a hand or something else, to block off the water that is flowing and being collected from every side, whereas when it is released there is more than there was at the start? And just as it can be checked off by the hand, so it can also be checked off by the breath, as in a water-clock, and again as with the bladder, for it takes it up within. So likewise, when there is much motion, the breath is caught and held within; that is also why the veins are stretched taut, since the moisture is unable to get out. And the moisture, being held back in a mass, when the breath is released, comes out all at once. Why do people sweat less after eating, once they have drunk? Is it because the food draws the moisture to itself, like a sponge falling into it, and it is no small part of the body's mass that can check the onward rush, just as in the case of flowing streams, taking in nourishment blocks the passages?
10| Why do people in a state of anxious tension sweat in the feet but not in the face? For it would be more reasonable that, when the whole body sweats, the feet should sweat then most of all, since that place is coldest, which is why it sweats least. And doctors, in cases of illness, above all instruct people to wrap up the feet, because they are easily chilled, so that they readily cause the beginning of a shivering fit that spreads to the rest of the body as well. Or is it that anxious tension, too, is not a shifting of heat, as happens in fear, from the upper regions to the lower (which is also why the bowels are loosened in those who are afraid), but rather an increase of heat, as happens in anger? For anger too is a boiling of the heat around the heart; and the person in anxious tension is affected not through fear and chilling, but through what is coming. Why do people become very red in the face, yet do not sweat there? Is it because that part is heated more, so that the moisture in the face is dried up by the heat coming to the surface, while the moisture in the feet is melted away, because it is a smaller quantity there but greater than the natural and pre-existing amount? Why do people sweat more while asleep than while awake? Is it because the origin of the sweat is from within, and the inner parts are hotter, so that the inner heat, dispersing the inner moisture, excretes it? And it is because something always seems to be flowing away from the body, but because there is nothing for it to strike against and collect visibly, it escapes notice. A sign of this is that the hollow parts of the body are always sweating.
11| Why do people sweat more in sweating-rooms when it is cold? Is it because the heat does not travel outward on account of the surrounding cold, being checked by it, but, being wrapped up and remaining within, dissolves the moisture in us and produces sweat out of it? Why is the sweat that comes from running naked, even if less in quantity, more beneficial than that which comes from running in a garment? Is it because exerting oneself is, in general, better than not exerting oneself, and sweat that comes with exertion is better than sweat without exertion, and sweat that comes with more exertion is better than that with less? And the sweat of one running naked comes with more exertion, for unless he runs with a great deal of strain he cannot sweat while naked, whereas in a garment, even if he runs quite moderately, he quickly sweats because of the warmth from the garment. Also, those who run naked in summer become better colored than those who run in garments, because just as all who live in places with better ventilation are better colored than those who live in stifled places, so too a person himself, compared to himself, is better colored when he is, as it were, in good ventilation than when he is stifled and enclosed by a great deal of warmth, which happens more to the person running in a garment. For these same reasons, too, those who sleep for a long time have a worse color than those who sleep a moderate amount, for the sleeper too is stifled.
12| Why do people in the grip of anxiety sweat at the feet but not at the face, when in the rest of life we sweat most at the face and least at the feet? Is it because anxiety is a kind of fear before the start of an undertaking, and fear is a cooling of the upper parts? That is also why the faces of anxious people turn pale. But they move and kick about with their feet; for anxious people do this, and in a sense exercise themselves; and so naturally these parts, the ones they work, sweat — just as people also rub their hands together, crouch down, stretch out, leap up, and are never still, since they are eager to get moving toward the task, because their heat has collected in the region around the chest, which is more solidly fleshed. Hence, as the heat and the blood dart about in every direction, a dense and varied motion results. They sweat most at the feet because these work continuously, while the other parts of the body get some rest through changes of posture and motion.
13| Why in steam-rooms do people not sweat more when the fire is applied all at once, nor when it is kept continually smaller, but rather when it is being increased? For people sweat more in the steam-rooms when the fire is being built up gradually than if it had been that great from the very start. Is it that a great fire, taking hold of the flesh and skin from the first while they are still dry, burns them and bakes them hard like a shell, and once the flesh has become like that, it checks the sweat? Whereas a small fire relaxes the flesh more and makes it porous, and, as it were, works the interior like kneaded dough toward separation and expulsion of moisture. And with the flesh in this state, more fire brought in afterward, sinking into the depth of the flesh because of its porousness, evaporates the moisture already softened beforehand, and separating out its finer parts, drives it out together with the breath. Should one arrange to induce sweating more in summer or in winter? Is it that in winter the heat, being drawn together inside, concocts and turns to vapor the moisture within us, so that, since all or most of it is used up, none of it needs a corresponding excretion? Whereas in summer, since the heat escapes through the porous flesh, the moisture within us is concocted less, and so needs to be drained off; for if it remains there because of the season, it putrefies and produces disease. For everything that putrefies does so under the action of a foreign heat, whereas it is concocted by its own proper heat. In summer, then, the foreign heat prevails, which is why everything putrefies more readily then; but in winter the body's own heat prevails, which is why winter does not putrefy things.
14| Why, when sweats occur either from heat within or from heat striking in from outside, do we shiver at some sweats? Is it because, when they break out under the action of the internal heat, moving from a large space into a small one, they are compressed against what surrounds them and block off the heat's circuits altogether, and then shivering sets in — especially once the flesh has become thoroughly drenched and the heat is passing out through it? Whereas heat striking in from outside first rarefies the skin; then the heat natural to us, being separated off, produces the shiver. Why are hot sweats judged to be better than cold ones? Is it because every sweat is an excretion of some residue, and it is reasonable that a small residue should be thoroughly heated while a larger one is not heated in the same way, so that a cold sweat would be a sign of abundant residue? That is also why it points to more prolonged illnesses. Why, when sweats occur because of heat, do we sweat less in the presence of a great fire? Is it either because, the body being very greatly heated, the moisture is dissolved into vapor, or because, as the moisture escapes and quickly dries up all around, we fail to perceive it? Why, when the sun is heating more, if we have no covering... do sweats occur more for those wrapped up in cloaks than for the same in cloaks? About this too we shall say the same as for the previous question.
15| Why, though sharp motions seem to heat more and sluggish ones less, are uphill journeys, though more sluggish, more productive of sweat, and do they bring on shortness of breath, as though they heated more than downhill journeys? Is it because it is natural for heavy things to be carried downward, and contrary to nature to be carried upward? So the nature of the heat that carries us contributes no effort toward downhill travel, but on the uphill it continually does the carrying-work. So through this kind of motion the body is heated more, excretes more sweat, and brings on shortness of breath. The bending of the body in walking also contributes something on uphill journeys, by hindering the breath from passing straight through. Why, when sweats occur, is it not the case that the more clothes one piles on, the more those who pile on the most sweat? About this too we shall say the same as above. Why, though bodies are drier in summer than in winter, are we more disposed to sweat in summer? Is it because in summer, the body being porous, the body's natural heat is not held back much? So it dissolves the moisture into vapor. But in winter, the outer parts of the body being condensed, the natural heat, being held in in quantity, does not dissolve the moisture into vapor. Further, in summer we take in much liquid, but in winter the opposite.
16| Why do the sweats that occur spontaneously in healthy people seem inferior to those produced by exertion? Is it because exertions, continually draining off the excess moisture, render the flesh drier, so that the channels of the pores are healthy and, through the habituation of the heat, no blockage occurs; whereas the so-called spontaneous sweats, occurring of necessity, when, because the body's natural channels are thrown into confusion by too much moisture, the heat is not completely overpowered but is still able to fight back and excrete it — these reasonably appear as signs of disease? For at that time the body is chilled by more moisture than is proportionate to its nature, and the flesh, becoming waterlogged, takes on the worst condition for health. Why do sweats occur less in winter, and why do we not wish to induce them in the same way, even though bodies are more moist in winter? Is it that we sweat less because the moisture in winter has frozen and set very hard, and so is harder to dissolve? And we do not suppose one ought to induce sweating in winter, because such a condition is healthy. But whatever induces sweats melts and confounds the body's state; further, by making it more porous than is fitting and by separating off the internal heat, it makes that heat less, so that it is not equally able to be set in opposition to the surrounding cold; and the moisture from outside will more easily invade the body, since the pores are more open because of the sweat-inducing.